Legrand crofoot



L. CROFOOT.

Bevel.

Patented Aug. 26, 718 56.

u hugraphcr. Washington. D. c.

LEGRAND CROFOOT, OF SYRACUSE, NEW YORK.

& I

INSTRUMENT FOR LAYING OUT RAFTERS.

Specification of Letters Patent No. 15,600, dated August 26, 1856.-

To all whom it may concern.

Be it known that I, LEGRAND Cnorooa, of the city of Syracuse, in the county of Onondaga and State of Ney York, have invented a new and useful Improvement in Instruments for Laying Out Rafters; and I do hereby declare the following to be a full, clear, and exact description of the same, reference being had to the annexed drawings, making part of this specification.

In making my invention, construct the measure (A-B) of wood having the extremities plated with brass; make it in two parts with clasps (C) so arranged as to connect the two parts together and at the same time allow them to be drawn or extended lengthwiseby each part sliding through the clasp of the other part. The parts A-B of the measure may be made of any convenient length and divided into feet, inches, and fractions of an inch. Each end of the measure is provided with a bevel (DE) working upon a pivot Each end of the measure is also provided with a plate (F) (G) set at right angles with the measure, and each of the bevel plates (D and E) are also provided with similar plates connected with'the bevel by the sliding piece (I-I) and the set screws (JJ). The bevels may be held in the desired position by the set screws (K--K) acting on the arcs of circles L L which have their centers at H H respectively. These arcs may be so graduated that the divisions, and figures on that attached toE, may serve to adjust the instrument for laying off the lower ends of rafters for any desired pitch of roof while divisions with corresponding numbers running in the reverse direction upon the arc of the bevel D, shall indicate the properposition of D, to describe the perpenclicular line required for the upper end of the rafter when in position in the roof. Or the arcs maybe graduated in degrees of circles indicating the angles of the bevels at either end of the instrument for the purpose of laying off struts braces, 860. at any liable to change that relation. On applyingthe instrument to a rafter (O), the bevels serve to mark the side surfaces, while the squaring plates may be adjusted so as to mark the upper and lower surfaces.

After the instrument is adjusted so as to mark one rafter for being cut, it is obvious it will serve for marking or laying out any desired number of rafters of the same dimensions,

Plates (R and S) are attached to the square tongues, and are adjustable by the set screws (T and U). The plates are for the purpose of marking tenons on the ends of timber or rafters.

WVhat I claim as my invention and desire to secure by Letters Patent is 1. The combination of the adjustable expanding measure A B with the adjustable bevels D and E, constructed and arranged substantially as hereindescribed for the purposes specified.

2. And also in combination with the above the fixed square-plates F and G and the ad justable square-plates, sliding on the bevels D and E substantially as herein specified and for the purpose set forth.

LEGRAND CROFOOT.

Witnesses:

R. F. STEVENS, R. D. Snow. 

